SU1158802A1 - Mechanism of intermittent rotation and location of driver link - Google Patents

Abstract

MECHANISM OF PRERAST. ROTATIONS AND FIXEDS OF A LEADING LINK, containing a drive shaft, a flat cam placed on it with a working profile and fixing surface, a driven shaft, a rocker rigidly connected to it, carrying at least three rollers interacting with a cam, characterized in reducing the size and increasing reliability, the radius of the rocker rollers is equal to the center-to-center distance between the shafts, and the locking surface is located relative to the axis of rotation of the cam at a distance equal to the radius of the rocker roller.

Description

1115 The invention relates to mechanical engineering and can be used to drive actuators with an intermittent motion cycle. A known intermittent rotation and fixation mechanism comprising a drive shaft, a flat cam t with a working profile and an internal bore, with which the four rollers of the output beam of the driven shaft cooperate, providing a 90 ° angle of the rocker arm at one turn of the cam and the rigid fixation of the driven shaft fl}. The closest in technical essence and the achieved result is the mechanism of intermittent rotation and fixation of the driven link, which contains a drive shaft, a flat cam placed on it with a working profile and a fixing surface, a driven shaft, a rigidly connected shaft carrying at least three roller interacting with cam 2. The disadvantages of the known mechanisms are the large size and low reliability due to the low dynamic properties. The purpose of the invention is to increase reliability and reduce the size of Mexa. The goal is achieved by the fact that in the mechanism of intermittent rotation and fixation of the driven link containing the drive shaft, a flat cam placed on it with a working profile and fixing surface, the driven shaft is rigidly connected to it. carrying at least three rollers. interacting with the cam, the radius of location of the rocker rollers is equal to the center-to-center distance between the shafts, and the locking surface is located relative to the axis of rotation of the cam at a distance equal to the radius of the rocker arm. Fig. 1 shows a mechanism for intermittent rotation and fixation of a driven member, a longitudinal section; Fig. 2 shows section A-A in Fig. 3; Figs. 3-8 of the relative position of the cam and rocker arm at different stages of rotation during the cycle. The mechanism of rotational rotation and fixation of the driven link contains the leading 1 and the driven 2 shafts placed in the housing 3. On the driving shaft 1 there is a fixed cam 4 rigidly fixed, and on the 22 driven driven shaft 2 rigidly mounted KojpoMyulo 5, made in the form of three equally spaced circumferential arms 6, rigidly interconnected by a common hub 7. Each of the levers is provided with a roller 9 installed on the axis 8. The radius of arrangement of the rollers 9 of box 1 of 1 and 5 RP is equal to the distance H between the axes of shafts 1 and 2 of the mechanism. A stop 10, a spring 11 and a pin 12 are placed in the bore of cam A, and the distance M (Fig. 1) between the cam axis and the fixing surface 13 of the stop 10 is equal to the radius of the roller 9 of the rocker arm 5. The working profile of the cam 4 consists of three curved sections a -, 6-g and d-e and two sections B-e and z.-j with constant radii R and g. The mechanism works as follows. In the initial position, for example in. the moment of the end of the rocker arm 5 (fig.Z), two rollers interact with points a and i of the cam profile, and the third one with a stop 10. When you turn the cam 4 clockwise at an angle in the range of 0-90 °, the O.-J profile interacts with the roller associated with it and rotates the rocker arms g (Fig. 4), while the second roller rolls around without a clearance along the section of the pro. c B-g. , providing a geometric closure of the links of the mechanism. After turning the cam 4 at an angle of 90 (FIG. 5), all three rollers of the rocker arm 5 are in contact with different sections of the cam profile. When rotating the lance 4 in the section 90-180, the rotation of the cam is accomplished by influencing the profile d- on the mat a roller with him, and the geometric closure of the links of the mechanism is provided for a-, profile (Fig.6). In the process of turning the cam 4 at an angle in the range of 180-360 (Figs. 7 and 8), the height of the driven shaft 2 is accomplished due to running of the rollers 9 of the rocker arm 5 along the section of the profile with a constant radius R, and the geometrical closure of the links of the mechanism The section of the swiveling rocker is made by the interaction of the stop 10 with the third roller, whose axis in the period of the balance of the yoke is aligned with the axis of the drive shaft of the cam 4. After the process is completed, the stand (rotate the cam through an angle of 360 °) repeats in the specified sequence. The presence of a spring-loaded stop 10 provides automatic compensation for inaccuracies in the manufacture and wear of the engagement elements, as well as the backlash-free closing of the links of the mechanism in the area of a short distance. The high dynamic qualities and reliability of the proposed mechanism are ensured by the presence of tension in the places of contact of the rollers of the rocker arm with the cam profile. Depending on the start of the mechanism and the operating conditions, the cam can be provided with rigid stationary or adjustable locking surfaces instead of a spring-loaded stop 10. The invention can be used to drive the actuators of devices and machines with a deadly motion cycle, for example, to drive roller feeders Devices of sheet-stamping post press of automatic machines of the increased accuracy and high-speed.

Figg

Initial position

FIG A

5

FIG. 6

at

FIG. one

FIG. eight

Claims (1)

INTERMEDIATE MECHANISM. ROTATION AND FIXATION OF A SLAVE LINK, comprising a drive shaft, a flat cam placed on it with a working profile and a fixing surface, a driven shaft, a rocker rigidly connected to it, bearing at least three rollers interacting with the cam, characterized in that, in order to reduce dimensions and improve reliability, the radius of the rocker rollers is equal to the center-to-center distance between the shafts, and the fixing surface is located relative to the axis of rotation of the cam at a distance equal to the radius of the rocker roller. ω s: Fie. 1 1 1158802 2